Lubricant additives and preparation thereof



Patented July 23, 1946 UNITED STATES PATENT oF'F cE;f

2,404,446 H l LUBRICANT ADDITIVES AND PREPARATION THEREOF I- Eugene Lieber, WestNew Brighton, StatenIs'land; I t V p N. Y., and Aloysiuf's F. Cashman, Bayonne, N. J;

assignors to Standard Oil Development Company,a corporation of Delaware No Drawing. Application December 30, 1942, Serial No. 470,642 Y J 1 Claim. (01. zoo-"i251 j r This invention relates to improved extreme andthen allowing the mixture to settle into two pressure additives for incorporation in mineral layers, onethe extract phasejj (usually the upper lubricating oils torprepare lubricants especially layer) andlthe'other theraflinate phase (usuallyadapted'for operationunder extreme pressure, the'lower layer). Such a'batchextractionImay such as involved in the operatidn'ofhypoid gears behrepeated successivelyuntil the desired jsep+ usedinmotor vehicles, etc. 7 aration has been made bythevdesirediconstitul It has been known for some time thatmineral ems having good 1 stability and {go d extreme oils per se are not capable of withstanding the pressure lubricating. characteristics, which gengreat pressures encountered between engaged orally are "constituents having about 1 to 10%: of metal surfaces in various types of machines, etc., sulfur and about 30 to 40% of 'chlorine,as1dissuch as hypoid gears; but that additives capable ting-uishedf'rom' the undesirable fraction" which of increasing their load carrying capacity to a generallylhasflsuch poor st'abilitya's to be actually satisfactory degree can be made by' making insolubleinmineral lubricatingoilsland whichpetroleum hydrocarbon derivatives containing generally'ha's'rnorethan 110% ofisulf ur. and less both sulfur and ah'alogen'suchas chlorine. Such than 30%;of7chlorine. Thistyp of extraction additives may be made, for instance, as described maybe illustrated by the usejof isopropylalcohol in U. S. Patent 2,124,598, by chlorinating a pe-' I as the extracting solvent, in which case the 'detroleum hydrocarbon fraction such. as kerosene sired constituents are dissolved preferentially in or paraffin wax and reacting the resultant .chlothe solvent and therefore are contained in the rinated hydrocarbon product with alkaline polyextract phase while' the undesired constituents sulfide. 'Other related products are made by remain in the raftinate phase. 7 H reacting a. chlorinated l kerosene with alkaline Such solvent extraction may be carried "out xanthates, alkaline-'thiocyan'ates, alkaline mereither by batch operation usingone or a plurality captides, etc; Although such extreme. pressure of successive batches or stages, using either fresh additiveshave in" general been quitesatisfactory, or recycled solvent, or it maybe carried outcomit has been observed occasionally that some of tinuously; and it may also be carried-out concurthese additive have shown a'slight' tendency torently or" countercurrently. A preferred I proward instability during: storagefapparently due cedure is continuous countercurrent solvent ex! to" the presence thereinfofi constituents, which traction, illustrated by feeding a solvent such as either are not as completely soluble 'or' tend to isopropyl alcohol into the base of-a verticalfitower become insoluble and settle out'during storage. and-feeding'the original or c-rude extreme pres- It is one object of the present invention to sure additive (-which' has'ahighergravitythan prepare extreme pressure additives which are the alcohol) near the top thereof sozthat itzwill substantially free from any constituents which descend while the alcohol is ascendin th e are either insoluble or tend to' become insoluble result that, a countercurrent contacting is 'carduring storage. Another object of the invention riedout-continuously, the alcohol extract .phase is to improve the load carrying'capacity of 'exbeing removed icontinuously from the topof the tremepressure additives; l tower and the undesired insoluble rafiinate being Broadly the invention T'coinprises refining peremoved continuously at the bottom of the tower. troleum hydrocarbon derivatives which-contain vgm Another way of carrying out the inventionlis both sulfur and halogen by contacting them'with to mix the crude extreme pressure additive with a selective solvent havin'gfa preferential solvency a suitable solvent, heatto the point of complete for relatively low-sulfur constituents as compared solubility or miscibility; and ;}thenf;either; cool to relatively high sulfur constituents. and/or add 'a precipitating agent orantisolyent The invention may be'carried' out in a number ,45 to cause the separation into two liquidphasesf of different-ways such as by contacting the. or-

The material to; be used asj'jsolvent mayfbe iginal'extreme pressure additive, i. e., the:' crude selected from a wide variety of substances; {Expetroleum hydrocarbon derivative fraction 1 conainples include the. lower alcohols suchas iso-a taining both sulfur and halogen, with a selecpropyl alcohol, amylalcohol, butyl alcoholiethyl' fivesolvent; preferablywith suitable -agitation, Q9 alcohpl; letc.', iorfjvarious,other types;pr p ygen 3 V containingaliphatic organic compounds, such as ethers, e. g., di-ethyl ether, di-isopropyl ether, etc., ketones, e. g., acetone, methyl isopropyl ketone, methyl isobutyl ketone, etc., esters, e. g., ethyl acetate, isopropyl acetate, amyl acetate, methyl propionate, isopropyl butyrate, ethyl valerate, etc., or organic acids, such as acetic acid, chloracetic acid, propionic acid, etc. Other substances known more or less as aclass-of selective' solvents "having a preferential solvency for aromatic and unsaturated hydrocarbons may be used such asqphenol, liquid sulfur dioxide, aniline,

furfural, dichlor diethyl. ether, nitrobenzene, etc.-

A still different type of solvent which may be used comprises liquefied normally gaseou 'hydrocarbons such as butane, propane, ethane, etc, In carrying out the solvent'extraction with any of the'various types of solvents mentioned above,

instead of using a single solvent, two 'or more 7 different solvents either within the same'class of substances or in different classes may be used. Also, if desired, various substances, known as anti-solvents in the lubricating oil solvent extraction art, may be used such as water, glycols, liquid anhydrous ammonia, etc.; such materials are preferablyused iri relatively small amounts to 'modify the solvency characteristics 'of one of the other .types 'of' solvents mentioned above.

A still 'furtheralternative procedure is 'to dilute the crude'extreme' pressure additive with a light hydrocarbon liquid, such as'a refined naphtha,

before contactingit with the, selective solvent. {After the extraction has been completed, the

4 rial, referred to as crude extreme pressure agent A, was contacted very vigorously with 1,000 cc. of isopropyl alcohol (91% grade) in a separatory funnel and the mixture settled at room temperature for 48 hours. The following separation was effected.

Extract phase (upper layer) =1,040 cc. Rafiinate phase (lower layer): 960 cc..

The extract phase was-distilled in order to remove the isopropyl alcohol, taking off" the last traces under high vacuum ona water bath. An extract weighing ll2'grams was obtained. This will tbe identifiedas First extraction product. 7 The rafiinate phase obtained above was contacted very vigorously with 1,000 cc. of 99% ispropylyalcohol by contacting vigorously in a sep- 7 aratory funnel and the mixture settled for 24 hoursat room temperature. The following separation was effected:

-Second extract phase (upper layer) l,240 cc.

solvent maybe removed from the solvent phase and this'may be done either after individual steps in a prooess'involving'seve'ralstages,or'at'the end of a cumulative or-countercurrent operation.j

In carrying out the invention the proportions of materials to be used will, ofjco'urse, vary within a Wide range depending upon the nature of the crude extremepressure additive beingtreated, the, type of solvent, and anti-solvent (if any) used, as'well asupon the temperature and pressure conditions used and the degree of refinement desired; However, usuallyabout A; to 10 parts of solvent should be usedto one part by volume .of crude extreme pressure additive, and generally I about 1 to 5 volumes of-solvent to one of extreme ,pressure additive will be found to give satisfac- I .tory results} The temperature used maybeeither room temperature or above or below room tem- Second raffinate phaseilower layer): 710cc.

The second extract phase was" distilled as before, and a Second extraction product weighing 363 grams was obtaine d.- v

The Second raffinate phase was contacted vigorously again with 1,000 cc. of 99% isopropyl alcohol as before. After settling for '72 hours at room temperature the following separations were obtained:

Third extract phase (upper layer) =l,220 cc. hird raflinate phase; (lower layer) 500 cc. 7

The third extract 'phase was distilled as before to remove isopropyl alcohol and a Third extraction" product weighing 201 grams was obtained. The Third raflinate phase obtained above'was contacted vigorously again with 1,000 cc. of99%- perature,-and generally a temperature between room temperature and 250 F. will be'satis factory. The pressure may be atmospheric or above or below atmospheric, a slight superatmospheric pressure being, of course, necessary when using volatile materials, such as liquefied normally gaseous hydrocarbons.

The objects, advantages and details of the in- V vention will be better understood froma consideration' of the following specific examples which.

areloffered by Way of illustration but withouti'the intention of limiting the invention specifically thereto. r Y 1' v. 7.2' :EXAlVlIPLEfiL 'A sample of commercial extreme pressureadditive marketed under the trade name fPa'rapoid- '10,.frriade'by' chlorinating kerosene atatempera= ture/of about 175"F; to a chlorine fcontent of about 210 %.1chlorine, andreacting theresulting chlorinated kerosene with sodium 'polysulfi'de',jand

lalso ffouhdito contain 7.3 'sul'furiand"l33'.0,% chlorine, wasused asraw material according to thisinvention. About 1;;200grams of thisniate- 75 isopropyl alcohol. After settling for 24 hours the following separation was obtained.

Fourth extract phase (upper layer) 1,-l2 0 cc. Fourth raffinate. phase (lowerlayer): 360cc.

Fifth extract phase layer) ,=1,600 .cc. Fifth rafiinate phase (lower layer): 260cc, The fifth rafiinate phase 'wasfound to be extremely viscous. I

"Thffifth extract phaselwa s distilled as before to remove isopropyl alcohol and a :,Fifth extrac tionf" product weighing 919 jg'rarnjswas obtained; The *fifth rafiinate phase was. also subjected :lZQ

. distillation and 'a' ffinal rafiinate :product-weigh-j i'ng 313 grams and consisting, of anextremely viscous tar-like material .wasobtained, 5 7

The 'extract'products and the final railinate product were tested for the followin' points?" Solubility a 10% Catamarangramme BrightlStock Analysis forg-sulfurandchlo ne Extreme pressureiproperties as;;-measured-; by

machine The "data obtained are summarixed 'i- TABLE 1 L SolWm e 'tm tion p EXAMPLE Per t v .Analysis j Solubility characteristics Exfrdmfl Fraction om pressure yield 1 properties 1 g g f 5% blend in Varsol 1 f SAE No.

Original unextracted extreme pressure agent A- 7. 3 33.0 Cloud and sediment Cloud and sediment.-. 320 First extraction product 9. 4 1.9 35.0 Clear Clear 400 Second extraction product 23. 6 3. 2 35. 7 363 Third-extraction product" 16. 8 V 3.4. 38. 0 425 Fourth extraction product. 11. 2 3. 3- 36. 0 390 Fifth extraction product. 823 5. 6 35. do 398 Rammm 26. 2 17. 0 24. 4 Heavy tarry sediment.

1 These are weight yields based on the original unextracted Parapoid-lo.

1 10% blend of particular fraction in Panhandle Bright Stock.

1 This test is described in the an. E. Journal, volume 39, pages 23 to 24 for the year 1936; a 1

It will be noted that all of the extracted phases isopropyl alcohol were-placed in a glass flask or have excellent solubility in both Varsol and Pan- 2 still, used 'afsreboilen. Heat was applied to the handle Bright Stock as contrasted with the origireboiler and the alcohol was vaporized. The vanal unextracted extreme pressure agent A. pors were led through an'insulated vapor line to Varsol is a refined varnolene in the heavy a'water 'cooled condenser and condensed and led naphtha boiling range. The data also bring out through a long-stemmed funnel to the bottom of the hitherto unknown fact that materials of the 25 the Parapoid l0 in theextractor. Theliquidal- Parapoid type containing only relatively small cohol then percolated upward through the -oil quantities of sulfur have even better extreme pres-' and formed an extract phase floating above the sure properties, as measured by the S. A. E. testrafiinate. The extract phase was siphoned coning machine, than the original unextracted matin'uously from the extractor through a lineconterial. It was hitherto believed that in order to 7m taining a vapor trap to the reboiler. In-the refunction asan extreme pressure additive the maboiler the alcohol was vaporized and repeated terial had to have a, relatively high percentage the cycle while the extract accumulated. The of sulfur in the molecule. a v process-W'as-continued for-16 hours, at which time It is believed that the improvements in soluit appeared to befairly complete. l

bility characteristics are due essentially to the Extract-and rafiinate were recovered by stripremoval of the heavy tarry material comprising ping off the solvent under high vacuum over a therafiinate. It was found that this material boiling water bath. They are compared below immediately precipitated not only from-Varsol with the originalParapoid-JO.

and Panhandle BrightStock but also from less highly refined petroleum oil fractions. 40 I Parapoid-IO me ma inate EXANIPLE 2 gins. retcovery 86- er cen recovery" r .5 I 28.

742 grams of commercial Parapoid, referred to Per cent Sulfur 5 M 13. as crude extreme pressure agent B, having the Per nt c11 2, 318

following analyslsz INSlECTIONS ON 0% BLENDS IN BANHANDLEV 7 S 84 BRIGHT STOCK 1 V l V D Extract Baffinate was subjected to solvent fractionationbythe pro- Soh1bimy{ .at 1o. Haze andshgh't clar and fieavyibud, cedure of Example 1, except that 99 isopropyl days. sediment. lag nt I?) heavyfii'sed- H 1111811 al oh l was used as solvent throughout. Copper strip at Slight stain Slight stain. Heavy mm,

The data obtained are summarized in Table 2. 212 F. I

TABLE 2 Solvent extraction of Rarapoid-IO EXAMPLE o. a

Analysis 7 7 Extreme ressure Percent Solubility characteristics 10% p I v properties Fraction y eld Percent Percent blend in Panhandle B. S. A 7 I v S 01 number Original unextracted material... 6 4 290 First extraction product 11. 8 1 8 372 Second extraction product. 35.9 4 l 388 Third extraction product 19. 6 4 1 443 Fourth extraction product 7. 6 5 0 34. 3 d0 418 Raflinate 19. 7 16 0 25. 0 Precipitates out as a tar-..

1 These are weight yields based on the original uncxtracted Parapoid-IO. 9 10% blend of the particular fraction in Panhandle Bright Stock. B This test is described in the S. A. E. Journal, volume 39, pages 23 to 24, [or the year 1936.

As indicated above, even in this small-scale EWLE 3 laboratory continuous extraction, the extract was 600 gms. of Parapoid-lO, containing 6.5% S remarkably superior to the original crude extreme and 32% Cl, were placed in a tall vertical glass pressure agent in regard to solubility and stacyllnder used as extractor and 1500 cc. of 98% bility, while the rafllnate'developed a heavy cloud and sediment in the solubility test and showed excessive copper COI'IOSiOI'I.

ried out on a commercial scale byusing a large vertical tower extractor, which may contain were subjected to solvent fractionation by the procedure of1Example 1, except that 91% iso- This type of continuous extraction can be fearf1 prqp'yl alcohol was used as solvent in the first "three extractions and 99% isopropyl alcohol in ':the fourth and fifth. The data is summarize b w-f v.

TABLE Solvent ertraction of Santapoid-A' Analysis Extreme p Perent S olubihtycharacterispressure Fraction 7 yield 1 V tics blend inPanproperties 7 7 Perscent Percent handle Bright Stock S. A. E. No.

a flpo 9. 6 31. 6 Oloudtandslight sedi- 40 men 1st extraction product 7 16. 6 6. 7 33. f1 Clearand no sediment; 380 p 2nd extraction product... 20. 4 6. 9 35. 2 do 365 3rd; extraction product. 116.0 7.3 '365 4th extraction product.- 42.3 10. 5 v 365 5th extraction product-" 9. 0' 11.9 do 405 These areweight yields based on original unextracted Santapoid.

extreme pressure agent into the-tower near the top thereof and feeding the alcohol in near the bottom of' the tower, continuously withdrawing the solvent extract phase at the top and the raffinate at the bottom of thetower, continuously passing the solvent'extract phase tp a-reboiler or.

still from which the alcohol is continuously Va.- porized and 'fro-m whichthe solvent free extract is withdrawn, the alcohol vapors being continuously'condensed and recycled to the extraction tow r.

A commercial extreme pressure agent known as Santapoid A gpreviously referred to above) is said QaH7-O OSENa O1!Ker0(Cl)4'-- 7 I v C aHr-O-C-S-Kero (O1) 585 gms. of this commercial Santapoid-A having the following analysisz V J 's.=9 6 Cl- '31.6-

plits out andthe Santapoid is 1 t 7 I. I 10% by weight of'the particular fraction in Panhandle Bright Stock. 7 i order' to obtain better. contacting 0f the up-goilng It is thus seen that by means Of the Present i and down-going liquids, ,then feeding the crude to the specific exam'ples which have been given" merely for the sake of illustration but only by the appended claim in which it is intended to claim all novelty inherent in the inventionas' well as all-modifications coming within the scope and spirit of the invention. a

We claim: 1

Process of preparing improved extreme pres sure lubricating agents, whichcomprises solvent extracting a chlorinated parafiin alkali polysulfide reaction product containing about 5 to 10% of sulphurand about toT, U% of chlorine at about room temperature with isopropyl alcohol of about 91% concentration, using about 1000 cc. of the alcohol per 1200 grams of material treated, separating the rafiinate phase from the extract phase, subjecting the rafiinate phase to three successive extractions at room temperature with isopropyl alcoholof about 99% concene tration, using about the same volume of solvent as in the first extraction phase, extracting the fourth raffinate at about F. with isopropyl alcohol of about 99%" concentration, and recoveri'ngthe "solvent from each of the extract phases and from the final raffinate phase.

EUGENE LIEBER. ALOYSIUS F. CASHMAN. 

